Like neighboring Thrace and Epirus, Macedonia has been, since the early Middle Ages, a meeting place of nations, a fact that has contributed in large measure to its complex and turbulent history. Macedonians first appear historically about 700 B.C. By about 400 B.C., they had adopted the Greek language and had begun to build a kingdom (Macedon) that was greatly enlarged by the conquests of Philip II (359–336 B.C.) and Alexander the Great (336–323 B.C.). In the 2d cent. B.C., Macedonia became a Roman province.
With the division (A.D. 395) of the Roman Empire, Macedonia came under Byzantine rule. Devastated by the Goths and Huns, it was settled (6th cent.) by the Slavs, who quickly made most of Macedonia a Slavic land. However, it continued under intermittent Byzantine domination until the 9th cent., when most of Macedonia was wrested from the Byzantine Empire by Bulgaria. Emperor Basil II recovered it (1014–18) for Byzantium, but after the temporary breakup (1204) of the Byzantine Empire during the Fourth Crusade, Macedonia was bitterly contested among the Latin Empire of Constantinople, the Bulgars under Ivan II, the despots of Epirus, and the emperors of Nicaea. It again became part of the Byzantine Empire, which was restored in 1261, but in the 14th cent. Stephen Dušan of Serbia conquered all Macedonia except for present-day Thessaloníki.
The fall of the Serbian empire in the late 14th cent. brought Macedonia under the rule of the Ottoman Turks, which lasted for five centuries. In the 19th cent. the national revival in the Balkans began; national and religious antagonism flared, and conflict was heightened by the Ottoman policy of playing one group against the other. Meanwhile the Ottoman Empire lost control over the major sections of Greece, Serbia, and Bulgaria, each of which claimed Macedonia on historical or ethnical grounds. In the Treaty of San Stefano (1878), which terminated the Russo-Turkish War of 1877–78, Bulgaria was awarded the lion's share of Macedonia. However, the settlement was nullified by the European powers in the same year (see Berlin, Congress of), and Macedonia was left under direct Ottoman control.
A secret terrorist organization working for Macedonian independence sprang up in the late 19th cent. and soon wielded great power. The komitadjis, as the terrorist bands were called, were generally supported by Bulgaria, which gained a major share of Macedonia in the first of the Balkan Wars (1912–13). Greece and Serbia turned against Bulgaria in the Second Balkan War, and the Treaty of Bucharest (1913) left Bulgaria only a small share of Macedonia, the rest of which was divided roughly along the present lines. Thousands of Macedonians fled to Bulgaria.
In World War I the Salonica (present-day Thessaloníki) campaigns took place in Macedonia. After the war Macedonia became a hotbed of agitation and terrorism, directed largely from Bulgaria. The population exchange among Greece, Turkey, and Bulgaria after 1923 resulted in the replacement by Greek refugees from Asia Minor of most of the Slavic and Turkish elements in Greek Macedonia. Charging that the Greek minority in Bulgarian Macedonia was being mistreated, Greece in 1925 invaded Bulgaria. The League of Nations, however, forced a cession of hostilities and awarded (1926) a decision favorable to Bulgaria.
Bulgarian relations with Yugoslavia (before 1929 the Kingdom of the Serbs, Croats, and Slovenes) remained strained over the Macedonian question. Frontier incidents were frequent, as were Yugoslav charges against Bulgaria for fostering the Internal Macedonian Revolutionary Organization (IMRO), a nationalist group that used violence, in Yugoslavia. Macedonian agitation against Serbian rule culminated (1934) in the assassination of King Alexander of Yugoslavia by a Macedonian nationalist at Marseilles.
In World War II all Macedonia was occupied (1941–44) by Bulgaria, which sided with the Axis against Yugoslavia and Greece. The Bulgarian armistice treaty of 1944 restored the prewar boundaries, which were confirmed in the peace treaty of 1947. The Yugoslav constitution of 1946 made Yugoslav Macedonia an autonomous unit in a federal state, and the Macedonian people were recognized as a separate nationality.
Tension over Macedonia continued in the early postwar years. During the Greek civil war there was much conflict between Greece and Yugoslavia over Macedonia, and the breach between Yugoslavia and Bulgaria after 1948 helped to make the Macedonian question explosive. However, with the settlement of the civil war and with the easing of Yugoslav-Bulgarian relations after 1962, tension over Macedonia was reduced. In 1990, Yugoslav Macedonia elected its first non-Communist government and the following year the Republic of Macedonia was born.